an autodidact meets a dilettante…

‘Rise above yourself and grasp the world’ Archimedes – attribution

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technomagic – the tellingbone

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weirdly wired – the first telephone

The telephone remains the acme of electrical marvels. No other thing does so much with so little energy. No other thing is more enswathed in the unknown.

Herbert Casson ‘The history of the telephone”, 1910. Quoted in “The Information”, J Gleick

I recently had a conversation with someone of my generation about the technology of our childhoods, and how magical they seemed to us. So let me start with the motor car, or auto-mobile. Our first family car was a Hillman Minx, which was bought in maybe 1964 or so, not too long after we arrived in Australia. The model probably dated from the early or mid-fifties – we certainly weren’t wealthy enough to buy a brand new car. But that didn’t make it any less magical. How was it that you could turn a key and bring an engine to life, and with a bit of footwork and handiwork get the beast to move backward and forward and get its engine to putter or roar? I hadn’t the foggiest.

Next in the mid-sixties came the television box, fired by electrickery. Somehow, due to wires and signals, we could see a more or less fuzzy image of grey figures from faraway, giving us news of Britain and the World Cup, and shows from the USA like Hopalong Cassidy and the Cisco Kid, all made from faraway – even one day from the moon – for our entertainment and enlightenment. Wires and signals, I mean, WTF?

Next we became the first people in the street to have our own tellingbone (or that’s what we proudly told ourselves, actually we had no idea). So people would ring us from the other side of town and then talk to us as if they were standing right next to us!! It was crazy-making, yet people seemed generally to remain as sane as they had been. I would lie in bed trying to work it out. So someone would dial a number, and more or less instantaneously a ringing sound would come out of the phone miles and miles away, and a person there would pick up this bone-shaped piece of plastic with holes in it, and they would talk into one end and listen through the other end, and they could hear this person on the ‘end of the line’ miles away far better than they could hear someone else talking in the next room, all thanks, we were informed, to those wires and signals again.

So, forward to adulthood. One of the most informative books I’ve read in recent years is titled, appropriately enough, The Information, by James Gleick. It’s a history of information processing and communication from tribal drumming to the latest algorithms, and inter alia it tells the story of how the telephone became one of the most rapidly universalised forms of information transfer in human history in the period 1870-1900, approximately. And of course it didn’t come into existence out of nowhere. It replaced the telegraph, the first electrical telecommunications system, itself only a few decades old. Previous to this there were many experiments and developments in the field by the likes of Alessandro Volta, Johann Schweigger and Pavel Schilling. Studying electricity and its potential was the hottest of scientific activities throughout the 19th century, especially the first half.

The telegraph, though, was a transmission-reception system run by experts, making it very unlike the telephone. Gleick puts it thus:

The telegraph demanded literacy; the telephone embraced orality. A message sent by telegraph had first to be written, encoded and tapped out by a trained intermediary. To employ the telephone, one just talked. A child could use it.

Nevertheless the system of poles and wires, the harnessing of electricity, and the concepts of signal and noise (both abstract and exasperatingly practical) had all been dealt with to varying degrees of success well before the telephone came along.

So now let’s get into the basic mechanics. When we talk into a phone we produce patterned sound waves, a form of mechanical energy. Behind the phone’s mouthpiece is a diaphragm of thin metal. It vibrates at various speeds according to the patterned waves striking it. The diaphragm is attached to a microphone, which in the early phones consisted simply of carbon grains in a container attached to an electric current, which were compressed to varying degrees in response to the waves vibrating the diaphragm, modulating the current. That current flows through copper wires to a box outside your home which connects with other wires and cables in a huge telecommunications system.

Of course the miracle to us, or to me, is how a sound wave signal, moving presumably more or less at the speed of sound, and distinctive for every human (not to mention dogs, birds etc), can be converted to an electrical signal, moving presumably at some substantial fraction of the speed of light, then at the end of its journey be converted back to a mechanical signal with such perfect fidelity that you can hear the unmistakeable tones of your grandmother at the other end of the line in real time. The use of terms such as analogue and digitising don’t quite work for me, especially when combined with the word ‘simply’, which is often used. In any case, the process is commonplace enough, and has been used in radio, in recorded music and so forth.

It all bears some relation to the work of the greatest physical theorist of the 19th century, James Clerk Maxwell, who recognised and provided precise relationships between electrical impulses, magnetism and light, bringing the new and future technologies together, to be amplitude-modified by engineers who needed to understand the technicalities of input, output, feedback, multiplexing, and signal preservation. But as the possibilities of the new technology expanded, so did technological expertise, and switchboards and networks became increasingly complex. They eventually required a numbering system to keep track of users and connections, and telephone directories were born, only to grow in size and number, costing acres of forestry, until in the 21st century they didn’t. I won’t go into the development of mobile and smartphones here, those little black boxes of mystery which I might one day try to peer inside, but I think I’ve had enough armchair demystifying of the technomagical for one day.

Yet something I didn’t think of as a child was that the telephone was no more technomagical than just speaking and listening to the person beside you. To speak, to make words and sentences out of sounds, first requires a sound-maker (a voice-box, to employ a criminally simplistic term), then a complex set of sound-shapers (the tongue, the soft and hard palates, the teeth and lips) into those words and sentences. Once they leave the speaker’s lips they make waves in the air – complex and variable waves which carry to the hearer’s tympanum, stimulating nerves to send electrical impulses to the auditory cortex. This thinking to speaking to listening to comprehending process is so mundane to us as to breed indifference, but no AI process comes close to matching it.

References

The information, James Gleick, 2011

https://electronics.howstuffworks.com/telephone1.htm

https://www.antiquetelephonehistory.com/telworks.php

https://www.thoughtco.com/how-a-telephone-works-1992551

Written by stewart henderson

March 1, 2019 at 4:31 pm

Palestine 2: more recent ancient history

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The Temple Mount, Jerusalem

Jacinta: So the so-called Kingdom of Judah, from archaeological evidence, was not a particularly developed region, from a modern perspective. Jerusalem, always regarded as its most significant city, and central to all Zionist aspirations, came into being as a small village between 5000 and 4500 years ago. From about 4000 years ago, it seems to have been a vassal state of the Egyptian empire, but there’s scant archaeological evidence from the period, though there was clearly an increase of building construction under Ramesses II a little over 3200 years ago. Some 2700 years ago, the region became a part of the Assyrian empire, and then the Babylonians conquered the region only a century or so after that, largely destroying Jerusalem.

Canto: Right, and the Babylonians brought about a diaspora of sorts, which was soon reversed when Cyrus the Great of Persia defeated the Babylonians and allowed the Jews to return and rebuild their temple. Now this temple was a symbol of Judaism, and its destruction by the Babylonians struck at the heart of their religion, suggesting that it was well established 2600 years ago…

Jacinta: Yes, we’ll get back to the actual population of the region and their religion shortly. Persia remained in control of Judea until the time of Alexander the Great 2350 years ago (we’re avoiding the BC/AD designations) and remained under the control of his Seleucid successors until a local revolt led by Judas Maccabeus gave it semi-independence for a time under the Hasmonean and Herodian dynasties. The Romans by this time were the great power, and Judea became a client state, but when the population rose in revolt 1950 years ago, Jerusalem was sacked, and, after another revolt 70 years later, the troublesome province became an increasing target of Roman authorities, leading to a major diaspora that wasn’t reversed until the 20th century.

Canto: And that’s when our story really hots up, but getting back to that temple – you know it was built on this supposedly triple-holy site called the Temple Mount, current home of the Al-Aqsa Mosque and the Dome of the Rock, both of which are very holy of holy to Islam. Of course it’s no accident that Moslems built this dome about 1320 years ago just where the second Jewish Temple had stood…

Jacinta: Which, by the way, is the very place where, so says fundamentalist Judaism, their god created Adam, haha.

Canto: Yes yes and where he created the World as well, for old Adam to stretch his legs in. I mean it’s typical for a new religion to set its base camp on the ruins of an older one – just as the Christians did at ‘pagan’ sites when the Roman Empire turned Christian. But let’s look briefly at the history of the temple itself, since its first construction might be said to mark the beginning of Judaism as an organised religion. It has been called Solomon’s Temple, and there’s much bullshit in the Old Testament about Solomon being the ruler of a mighty empire, but absolutely no evidence has been found of his existence outside of those texts. My uneducated guess was that he was a local chieftain grossly exaggerated in his power by Old Testament propaganda. He supposedly lived around 2900 years ago, so believers assume the temple was built around that time. It’s noteworthy that the Israelis haven’t allowed any archaeological research to be done at the site for decades. But let’s be generous and assume from their own stories that Judaism is about 3000 years old.

Jacinta: And it seems that one of the tenets of Zionism is return to an ancient homeland. But a homeland isn’t a nation, quite. Australia’s Aborigines have had a homeland here for up to 60,000 years, but they didn’t have a nation in the modern sense of a state with institutions of government etc. Some Zionists, especially the religious ones, would use their holy books to argue for having an ancient nation-state under David and Solomon etc but that doesn’t sort with any evidence. Other Zionists though would argue that the region was overwhelmingly Jewish before the diaspora caused by Roman repression. That would be the basis of their demand for the creation of Israel as a nation, right?

Canto: That and their claim to be a uniquely oppressed people in their adopted countries, which was made more cogent after the Holocaust. The problem of course is that the region, one of the oldest humanly inhabited regions in the world, has never been exclusively Jewish, or Israelite or whatever you want to call it. Was it overwhelmingly Jewish during early Roman times? Perhaps so – I’m certainly willing to concede that, but I’m not sure what that counts for. The British Isles 2000 years ago, when Romanisation began there, was predominantly made up of Celtic tribes, migrants from Europe. The USA at that time was settled by a number of highly developed regional cultures, that tend now to be grouped under the heading ‘native American culture’. The Celts don’t have a nation, nor do the native Americans, or the Kurds, the Catalans, the Rohingyas…

Jacinta: But some of them have put forward cogent arguments for their own nation-state.

Canto: Yes, but the Zionist movement and its arguments were different – not necessarily more cogent – for a number of reasons. Zionism had a more international feel, due to the diaspora. It was locally active and felt in many parts of the world, unlike say, the Catalan movement. Also, It was a call to ‘return’ of a profoundly oppressed people – and this was before the rise of Nazism, after which it was able to take advantage of western guilt big-time. And for the religious Jews there was the whole thing about Jerusalem and the temple…

Jacinta: Okay, so we’re going to switch to the modern situation, but before that let’s look to the distinction made between Sephardic and Ashkenazi Jewishness. Ashkenazi Jews currently represent around three quarters of the Jewish population. The Sephardim are descended from those who settled in the Iberian Peninsula from the time of the diaspora – Roman times – but were then infamously expelled from the region under the Alhambra Decree of Ferdinand and Isabella in 1492, and a similar decree by the Portuguese monarchy in 1496.

Canto: Not to mention the 1290 expulsion of the Jews from England under Eddie I. They all appeared to say ‘Go East, young Jew, or we’ll have your guts for garters’, or words to that effect.

beating up on Jews in 13th century England – the design on the central figures’ robes represent the twin tablets brought down by Moses – 5 commandments on each?

Jacinta: The Jews descended from those who remained in the Levant and the Middle East during the diaspora are called Mizrahi Jews. The Ashkenazim’s descent is complicated. Actually the whole story is really effing complicated. For example the Ashkenazim were also pushed eastward during the late Middle Ages due to persecution. By the early Middle Ages they had settled in Northern and Central Europe, for example in settlements along the Rhine, where they developed the Yiddish language, from German mixed with Aramaic, Hebrew and other Eastern elements.

Canto: Yes, and they were pushed eastward, but also pushed into being more integrated into local cultures. This led to a kind of modernising movement, a Jewish Enlightenment known as the Haskalah, which revived Hebrew as a literary language.

Jacinta: But the point is that the Ashkenazim were, according to some observers, at the greatest remove from the Jews of the old spiritual homeland, due to their European integration and their Enlightenment values. On the other hand, it was above all the Ashkenazim who suffered under the Holocaust. So there was this post-Holocaust tension in the west between relieving itself of its guilt by acceding to the, largely Ashkenazi, push for occupation of the Southern Levant, there to recreate the nation of Israel, and questioning the bona-fides of their claim to this land.

Canto: Yes, and as a sidebar to all that, Paul Heywood-Smith claims in The Case for Palestine that there’s ‘considerable evidence’ that the Ashkenazim are ‘substantially derived from the conversion of the Khazars to Judaism in or about 805 CE’. He goes on:

The Khazars were Turkish nomads who occupied that land between the Black and Caspian seas (called the Caucasus today), including parts of eastern Turkey, north-west Iran and Georgia. Khazaria seems the likely source of the Jewish influx into Russia, the Ukraine, Poland, and Eastern Europe – and from there, into Western Europe.

But the authors of the Wikipedia article ‘Khazar hypothesis of Ashkenazi ancestry’ claim there is ‘meagre evidence’ for the hypothesis. In any case, the controversy is an indication of how fraught the Zionist issue is. You could say the Jewish claim to the Palestinian lands is stronger than the British claim to Australia ever was, but then the eighteenth century was a lot more lawless about such things than the twentieth, and a lot more contemptuous of native claims to their own land, insofar as they ever even considered the matter. In today’s more human rights oriented world, the fact that there were non-Jewish Palestinian people living in Palestine for centuries before the Zionists started making their claims in the late nineteenth century makes what has happened in recent history to create and maintain the state of Israel a source of concern to many of us. After all, we could have been one of those Palestinian people.

References

https://en.wikipedia.org/wiki/Khazar_hypothesis_of_Ashkenazi_ancestry

https://en.wikipedia.org/wiki/Haskalah

https://en.wikipedia.org/wiki/Kingdom_of_Judah

https://en.wikipedia.org/wiki/Ashkenazi_Jews

https://en.wikipedia.org/wiki/Sephardi_Jews

https://en.wikipedia.org/wiki/Mizrahi_Jews

Paul-Heywood-Smith, The Case for Palestine, 2014

Written by stewart henderson

January 21, 2019 at 3:06 pm

Palestine, an introductory dialogue, trying to sort out some ancient history

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Ancient Palestine/Canaan

Canto: Currently I’m reading stuff about Palestine, and wondering why it is that the Palestinian people and their plight appears to be so ignored in the west, at least by governments, and certainly by the Australian government, whether conservative or liberal. We seem to follow the USA rather religiously on this matter.

Jacinta: Yes, I believe the USA is nowadays firmly captured by the Jewish lobby, a far cry from the days when anti-semites like Henry Ford and Charles Coughlin were feted as American heroes.

Canto: Well I think you mean a certain kind of Jewish lobby – maybe better to say the Zionist lobby. But we’ll explore such terms as zionism and anti-semitism in the course of these dialogues, which given the complexity of this issue, and its rich but sad history, will probably cover several if not scores of blog posts…

Jacinta: My god.

Canto: Well I don’t know about your god but certainly the Jewish god will play his role, along with the Arabic god, but hopefully not too big a role since they’re arguably the same person, which would just confuse everyone.

Jacinta: So is Palestine considered a nation? I believe Australia is playing Palestine in the Asian Cup tonight, so doesn’t that prove that Palestine is a nation?

Canto: Maybe it proves that FIFA thinks Palestine’s a nation, so good on them for that, but certainly Israel doesn’t recognise Palestine’s nationhood. The fact is that a clear majority of UN member countries recognise Palestine as an independent state – essentially, a nation – but the situation on the ground is that this ‘state’ is broken into two unequal bits, the Gaza Strip on the Mediterranean coast to the south, and the much larger West Bank region, which sort of includes the highly contested city of Jerusalem. The West Bank is more or less completely occupied by Israel, apparently against international law, and Jewish settlements are continually being built there, again illegally, but with the clear consent of the Israeli government. The Gaza Strip is under Israeli blockade, so the people there don’t seem to be regular members of any kind of independent state that’s worthy of the name.

Jacinta: Yes, and, looking at a map of the nations that recognise Palestine, Sweden and Iceland appear to be the only Western European nations that do so. Western Europe, along with other nations with a European history such as Australia, New Zealand, the USA and Canada, are siding with Israel in opposing Palestinian nationhood. Interesting, because those are the nations that seemed most invested in setting up Israel after WW2, the nations with sizeable Jewish populations, right?

Canto: Yes, though the case of Russia is interesting. It has, or had, a large Jewish population, but anti-semitism, or anti-Jewish sentiment, to be euphemistic, has long been a feature of Russia (now officially known as Putinland). So it’s hardly surprising that Putinland supports Palestine.

Jacinta: Of course Putinland’s official policy would simply be ‘take the opposite side from the USA in all foreign affairs issues’.

Canto: That’s true too. But we need to understand the history of the Levantine region, and something of the history of the Jews, and the history of European colonialism – the tendency of powerful and ambitious nations, some of them not so ancient themselves, to draw up the boundaries of new nations – Afghanistan, Iraq, Israel etc – for more or less self-serving reasons, in order to understand what’s at stake in this conflict.

Jacinta: So the Jews go back a long way and are traditionally associated with this region, right?

Canto: Yes, but you have to try and dissociate the story the Jewish people tell about themselves, specifically in the Torah or Pentateuch, the first five books of the Old Testament, and what we know of history, objectively speaking. After all, this is all about land, and who it belongs to.

Jacinta: Well, we’re both evidence junkies, so it’ll be interesting to see where the evidence takes us. But I must say that my own possibly naive take on land questions is that land in general, constantly changing over the millions of years that tectonics have operated on it, belongs to nobody but itself. We’re nowadays obsessed with private property, and land first and foremost. But in a million years who will own the land that people spill their guts over today?

Canto: Yes, but that’s taking a rather long view of things, and we humans aren’t much into that. So let’s take a slightly shorter view and go back a few thousand years. The region currently in dispute was then known as Canaan. Now of course there were no defined boundaries to this region, and it wasn’t anything like an organised state, so the term Canaanites referred to an agglomeration of peoples with a variety of gods, beliefs and practices. Generally, though, they spoke a Semitic language…

Jacinta: Right, and this is interesting, in relation to the term ‘anti-semitism’. Hebrew is a Semitic language, but so is Arabic, which is much more widely spoken today, so to call Arabic people ‘anti-semitic’ doesn’t make much sense in the proper understanding of the term, though of course many Arabic people are anti-Jewish. But the term semitic is quite recent, first coined by German historians in the late 18th century, based on the Koine Greek pronunciation of Noah’s son Shem. It’s based on the proto-alphabetic scripts used by these languages – among the oldest written languages in the world.

Canto: So the Canaanites were polytheistic, and only a few of their gods are remembered today – Baal, Moloch and El, for example. The latter was a supreme god and might have been the model for Judaic monotheism, but I don’t want to get into that. The real point is that a diverse lot of people lived in the region of the southern Levant, or ancient Canaan. So let’s start the story some 3,400 years ago when various powerful empires or civilisations converged in terms of their interest in this region – the Egyptians of north Africa, the Hittites of Anatolia (modern Turkey), the Assyrians of Mesopotamia and the Mittani of the northern Levant and southern Anatolia. Now, we can get bogged down for ages in exploring the cultures, lifestyles and languages of these Canaanites…

Jacinta: Yes, let’s do so – I want to be thorough.

Canto: Well, however intrinsically interesting it all is, I’m not sure if it helps us to understand the current disaster in the region.

Jacinta: I’m sure it will – it’s just that understanding might not solve the situation. The people with the power today don’t much care about understanding. Anyway, you’ve started at 3400 years ago, and of course the land had been inhabited for thousands of years before that. Judaism presumably didn’t exist at that time?

Canto: No, it’s generally believed to have emerged later. The Torah, the first-written of its essential texts, was written between 2600 and 2400 years ago according to most scholars, presumably based on stories handed down about Jewish history – but many of those stories, such as that the Jews were once the captives of the Egyptians and escaped to the ‘promised land’ where they proceeded to slaughter its inhabitants, aren’t backed up by much in the way of archaeological evidence.

Jacinta: I suppose what I’m trying to get at is – when, if ever, did the region known as Canaan become something like ancient Israel, or Judaea, with a population that professed Judaism, predominantly?

Canto: Well, it’s very confusing. The land of Canaan, which we might call the Levant, was more or less the same as the region called Phoenicia by the Greeks, as far back as Homer, and we’re not sure when, or whether, Homer existed. But the Greeks also used the term ‘Palestine’, at least from the time of Herodotus 2500 years ago. These different names probably derived from different local languages. The Hebrew Bible – the Old Testament – doesn’t mention Phoenicia, which appears to be more a reference to the northern Levant – perhaps modern-day Lebanon. However, it has to be remembered that the Old Testament may be a guide but can’t be relied upon as serious history.

Jacinta: So how can we test the Zionist claim that this region is their natural homeland?

Canto: Well I’m trying to get to that, but the difficulty is that Zionism tends to be an exclusivist, nationalist movement, sometimes with religious overtones, and we’re inclusivist, transnational humanist types, so I’m struggling against my biases to give a fair rendering of the history. So let’s look at Judea, or Judah – and even that is confusing because Judea is a modern or revived term for a part of southern Palestine, and Judea is a Graeco-Roman adaptation of the term Judah, which refers to a territory of one of the Israelite tribes, later called the Kingdom of Judah, associated with such names as David and Solomon. However, insofar as the Kingdom of Judah existed, it was a small, sparsely populated mountain region of the southern Levant between Samaria in the north, the Dead Sea in the east, and the ‘Phillistine States’ in the west. I should point out that the Samaritans, a tiny ethnic group still in existence today, have their own religion distinct from Judaism, though they like to think it’s the true Judaism, as is the way with religious disputes between neighbouring tribes. The Phillistines were supposedly an Aegean people who settled in the region now more or less covered by the Gaza strip a little over 3000 years ago. According to the Hebrew Bible they were constantly doing battle with the Israelites, so you could say that the Israeli-Palestinian conflict is just a continuation of a tradition.

Jacinta: Haha that’s not funny. I can’t wait to hear more next time…

Written by stewart henderson

January 16, 2019 at 11:48 am

Posted in Canaan, history, judaism, Palestine

Tagged with , ,

Archimedes, the Mathematikos and the birth of science

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Rise above yourself and grasp the world.

Archimedes (attributed: inscribed on the Fields Medal)

One of Archimedes’ most spectacular inventions, the gravity-defying spiral-in-a-cylinder, or screw – still effective

Canto: So we spent some time at the Waikato museum in Hamilton, braving the school holiday crowd to view an exhibition celebrating the work of Archimedes (c 287-212 BCE) and his fellow mathematikos, and noting how it inspired the likes of Leonardo some 1800 years later. So let’s talk about their breakthroughs and about why there was such a gap between their clever contrivances and the maths on which they were based, and the scientific revolutionaries of the sixteenth and seventeenth centuries.

Jacinta: These are intriguing and vital questions. Many modern scientists have been dismissive of the science of the ancient Greeks because they think of Aristotle as representative. I think it was Lawrence Krauss I heard complaining of Aristotle’s belief that women had less teeth than men – apparently he never thought to count them! But the fact is that, though Aristotle is sometimes known as the father of empiricism, he probably doesn’t deserve that title except in respect of ethics, and politics, which he based on what actually works for societies and city-states, which is why he collected and analysed their constitutions. The mathematikos, on the other hand, eschewed ethical issues in favour of mathematics – geometry in particular (think Euclid). And, especially in the work of Archimedes, they enjoyed phenomenal success in many practical areas.

Canto: Especially warfare apparently. It seems Archimedes in particular was called on more than once to defend his city, Syracuse, with war machines. In the blurb to the exhibition, they mention ‘torsion ballistae’. Can you please explain?

Jacinta: Well, I’ll tell you about the torsion siege engine. It replaced the earlier tension siege engine, possibly invented in Syracuse in the time of Dionysius the Elder (c 432-367 BCE) – so the engineering of weapons of war was already a big thing at the time. It was basically a massive catapult. The first torsion device of this kind is generally dated to the time of Philip II of Macedon, Alexander’s dad, circa 340 BCE. The first extant evidence of its use comes from a list of items in the arsenal of the Acropolis in Athens dating to 338-326 BCE. So what is torsion? It’s the energy created by winding something up, like a spring. In earlier times, human hair, horsehair and animal sinews were used for this purpose.

Canto: So plats give you energy?

Jacinta: Torsion basically means twisting. The Greeks apparently used specially cured sinew combined with human or animal hair to create a ‘torsion bundle’ – we don’t know what the exact recipe was – which was fixed to a wooden frame and could be twisted and released regularly via levers without breaking. But the key development was the mathematics of these devices. This military website describes:

The critical dimension was the diameter of the sinew “spring” or torsion bundle. For a bolt shooter, the ideal diameter was one-ninth the length of the bolt. For a rock thrower the ratio was more complex; the diameter (d) of the bundle in dactyls (about 3/4 inch) should equal 1.1 times the cube root of 100 times the mass of the ball (m) in minas (about a pound). Saddled with a numerical notation system even more awkward than Roman numerals, the Greeks developed sophisticated geometric methods to compute cube roots.

Canto: So how were these maths – these geometric methods – derived. Euclid was the great geometer of the time, wasn’t he?

Jacinta: Actually, though the exact time-frame of Euclid’s life isn’t known, his Elements came out after this invention, but before the work of Archimedes. Clearly it must’ve been drawn from earlier mathematikos, such as Eudoxus, who worked out, via an early version of integral calculus, that areas of circles relate to squares of their radii, and volumes of spheres relate to the cubes of their radii, and various other relations between volumes and dimensions of pyramids, cylinders, cones etc, which obviously had practical applications as described above.

Canto: Okay, so tell us about Archimedes’ particular contributions, and about why the great work of the mathematikos was apparently discontinued after Archimedes. Considering that the Roman Empire didn’t become christianised until some 500 years after Archimedes’ death, we can’t really blame the Christians – can we?

Jacinta: Well, I mentioned that early version of integral calculus. It was called the method of exhaustion, a kind of geometric calculus which Archimedes took further than anyone before him, both in theoretical terms and via practical applications. Now I’m far from being a mathematician, but I’ve come to appreciate the essentiality of maths in understanding our universe – so much so that I perhaps regret my lack of mathematical expertise more than I regret anything else in my old life. This is by way of saying that I won’t try to explain Archimedes’ maths – but an understanding of maths is essential to understanding the magnitude of his achievement.

Canto: Okay, so what about his inventions?

Jacinta: Well the key is the application of complex and what might have seemed pointlessly abstract maths about the relations of ‘perfect’ shapes such as spheres, cones and cylinders to real world problems and their solutions. The lever is a good example. Archimedes didn’t invent levers but he was clearly fascinated by them. And it shouldn’t take long to realise that they have immense practical applications. Doors are levers, as are nail clippers, nutcrackers and see-saws. Archimedes wrote what we now call a treatise, On the equilibrium of planes, to explain the maths behind them. But the best illustration of Archimedes’ combination of theory and practice is probably what is known as Archimedes’ principle, which essentially launched the field of fluid dynamics, or fluid mechanics:

the upward buoyant force that is exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces and acts in the upward direction at the center of mass of the displaced fluid.

It comes from another treatise of his, On floating bodies. Now let me see if I can explain this. Take an object, any object. The downward force exerted on it is its weight. Immerse it in water. It will float or it will sink, and even if it floats it’ll be partially submersed. The principle doesn’t apply to objects that sink, which will have a density of anything over and above a certain level which permits it to float – I think.

Canto: But that principle, though it comes from a treatise about floating bodies, doesn’t distinguish between floating and sinking. It says ‘fully or partially submerged’…

Jacinta: But an object can be fully submerged and still float. To sink means to continue in a downward direction.

Canto: I’ve found that an object that floats – I’m thinking of water as the fluid, and perhaps I shouldn’t – always seems to have a certain proportion above the water level. Think of icebergs, and human bodies. But I think I get it – the force that keeps you up and floating will be equal to the weight of the water your body displaces… So if I was ten kilos heavier, I would still float but the upward force acting on me would be greater, but not by ten kilos, rather by the larger volume of water my larger body displaces measured in kilos, or by some measure of force…

Jacinta: I don’t think that’s wrong, but I’m not sure if it’s right. The problem for me is that the principle as stated doesn’t specify a floating body, only a body immersed – partially or fully in a fluid. Think of a stone dropped in water. It sinks. To the bottom.

Canto: And if the fluid is bottomless will it just keep on sinking? It’s as if there’s no upward force acting on it at all, or very little. I’m imagining a bottomless column of still water here, not an ocean with its currents…

Jacinta: Ha, I was thinking of a bathtub, but with a bottomless well, it will depend on the density of the stone. I think at some point it’ll slow down and be suspended. I’m sure water pressure will play a role, and density – of the water. And density is somehow related to pressure, and I’m getting lost…

Canto: We may need to do a Khan academy course. But getting back to Archimedes and the mathematikos, why was so little of their work built upon, until Galileo and others became inspired so many many centuries later?

Jacinta: That’s possibly too long a story to go into here, not that I’m much equipped to tell it. It no doubt relates to the gradual decline of the increasingly dispersed Greek culture of the Hellenistic and post-Hellenistic era. I wouldn’t want to say Christianity was a major cause but it certainly didn’t help. By the time the Roman Empire became Christianised, the culture that created figures like Archimedes had long passed. Roman culture was a lot more militaristic and less speculative. Blue sky research wasn’t in vogue. Of course, why all this happened I wouldn’t venture to say without many years of research into the cultural changes then occurring. But the slowness of the scientific recovery, that I would attribute to Christianity, and later to the conservative turn in Islam that still prevents original science from being practiced in those countries where it holds sway.

Written by stewart henderson

May 2, 2018 at 9:13 pm

on electrickery, part 2 – the beginnings

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William Gilbert, author of De Magnete, 1600

Canto: So let’s now start at the beginning. What we now call electricity, or even electromagnetism, has been observed and questioned since antiquity. People would’ve wondered about lightning and electrostatic shocks and so forth.

Jacinta: And by an electrostatic shock, you mean the sort we get sometimes when we touch a metal door handle? How does that work, and why do we call it electrostatic?

Canto: Well we could do a whole post on static electricity, and maybe we should, but it happens when electrons – excess electrons if you like – move from your hand to the conductive metal. This is a kind of electrical discharge. For it to have happened you need to have built up electric charge in your body. Static electricity is charge that builds up through contact with clothing, carpet etc. It’s called static because it has nowhere to go unless it comes into contact with a positive conductor.

Jacinta: Yes and it’s more common on dry days, because water molecules in the atmosphere help to dissipate electrons, reducing the charge in your body.

Canto: So the action of your shoes when walking on carpet – and rubber soles are worst for this – creates a transfer of electrons, as does rubbing a plastic rod with wooden cloth. In fact amber, a plastic-like tree resin, was called ‘elektron’ in ancient Greek. It was noticed in those days that jewellery made from amber often stuck to clothing, like a magnet, causing much wonderment no doubt.

Jacinta: But there’s this idea of ‘earthing’, can you explain that?

Canto: It’s not an idea, it’s a thing. It’s also called grounding, though probably earthing is better because it refers to the physical/electrical properties of the Earth. I can’t go into too much detail on this, its complexity is way above my head, but generally earthing an electrical current means dissipating it for safety purposes – though the Earth can also be used as an electrical conductor, if a rather unreliable one. I won’t go any further as I’m sure to get it wrong if I haven’t already.

Jacinta: Okay, so looking at the ‘modern’ history of our understanding of electricity and magnetism, Elizabethan England might be a good place to start. In the 1570s mathematically minded seamen and navigators such as William Borough and Robert Norman were noting certain magnetic properties of the Earth, and Norman worked out a way of measuring magnetic inclination in 1581. That’s the angle made with the horizon, which can be positive or negative depending on position. It all has to do with the Earth’s magnetic field lines, which don’t run parallel to the surface. Norman’s work was a major inspiration for William Gilbert, physician to Elizabeth I and a tireless experimenter, who published De Magnete (On the Magnet – the short title) in 1600. He rightly concluded that the Earth was itself a magnet, and correctly proposed that it had an iron core. He was the first to use the term ‘electric force’, through studying the electrostatic properties of amber.

Canto: Yes, Gilbert’s work was a milestone in modern physics, greatly influencing Kepler and Galileo. He collected under one head just about everything that was known about magnetism at the time, though he considered it a separate phenomenon from electricity. Easier for me to talk in these historical terms than in physics terms, where I get lost in the complexities within a few sentences.

Jacinta: I know the feeling, but here’s a relatively simple explanation of earthing/grounding from a ‘physics stack exchange’ which I hope is accurate:

Grounding a charged rod means neutralizing that rod. If the rod contains excess positive charge, once grounded the electrons from the ground neutralize the positive charge on the rod. If the rod is having an excess of negative charge, the excess charge flows to the ground. So the ground behaves like an infinite reservoir of electrons.

So the ground’s a sink for electrons but also a source of them.

Canto: Okay, so if we go the historical route we should mention a Chinese savant of the 11th century, Shen Kuo, who wrote about magnetism, compasses and navigation. Chinese navigators were regularly using the lodestone in the 12th century. But moving into the European renaissance, the great mathematician and polymath Gerolamo Cardano can’t be passed by. He was one of the era’s true originals, and he wrote about electricity and magnetism in the mid-16th century, describing them as separate entities.

Jacinta: But William Gilbert’s experiments advanced our knowledge much further. He found that heat and moisture negatively affected the ‘electrification’ of materials, of which there were many besides amber. Still, progress in this era, when idle curiosity was frowned upon, was slow, and nothing much else happened in the field until the work of Otto von Guericke and Robert Boyle in the mid-17th century. They were both interested particularly in the properties, electrical and otherwise, of vacuums.

Canto: But the electrical properties of vacuum tubes weren’t really explored until well into the 18th century. Certain practical developments had occurred though. The ‘electrostatic machine’ was first developed, in primitive form, by von Guericke, and improved throughout the 17th and 18th centuries, but they were often seen as little more than a sparky curiosity. There were some theoretical postulations about electrics and non-electrics, including a duel-fluid theory, all of which anticipated the concept of conductors and insulators. Breakthroughs occurred in the 1740s with the invention of the Leyden Jar, and with experiments in electrical signalling. For example, an ingenious experiment of 1746, conducted by Jean-Antoine Nollet, which connected 200 monks by wires to form a 1.6 kilometre circle, showed that the speed of electrical transmission was very high! Experiments in ‘electrotherapy’ were also carried out on plants, with mixed results.

Jacinta: And in the US, from around this time, Benjamin Franklin carried out his experiments with lightning and kites, and he’s generally credited with the idea of positive to negative electrical flow, though theories of what electricity actually is remained vague. But it seems that Franklin’s fame provided impetus to the field. Franklin’s experiments connected lightning and electricity once and for all, though similar work, both experimental and theoretical, was being conducted in France, England and elsewhere.

Canto: Yes, there’s a giant roll-call of eighteenth century researchers and investigators – among them Luigi Galvani, Jean Jallabert, John Canton, Ebenezer Kinnersley, Giovanni Beccaria, Joseph Priestley, Mathias Bose, Franz Aepinus, Henry Cavendish, Charles-Augustin Coulomb and Alessandro Volta, who progressed our understanding of electrical and magnetic phenomena, so that modern concepts like electric potential, charge, capacitance, current and the like, were being formalised by the end of that century.

Jacinta: Yes, for example Coulomb discovered, or published, a very important inverse-square law in 1784, which I don’t have the wherewithal to put here mathematically, but it states that:

The magnitude of the electrostatic force of attraction between two point charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them.

This law was an essential first step in the theory of electromagnetism, and it was anticipated by other researchers, including Priestley, Aepinus and Cavendish.

get it?

Canto: And Volta produced the first electric battery, which he demonstrated before Napoleon at the beginning of the 19th century.

Jacinta: And of course this led to further experimentation – almost impossible to trace the different pathways and directions opened up. In England, Humphrey Davy and later Faraday conducted experiments in electrochemistry, and Davy invented the first form of electric light in 1809. Scientists, mathematicians, experimenters and inventors of the early nineteenth century who made valuable contributions include Hans Christian Orsted, Andre-Marie Ampere, Georg Simon Ohm and Joseph Henry, though there were many others. Probably the most important experimenter of the period, in both electricity and magnetism, was Michael Faraday, though his knowledge of mathematics was very limited. It was James Clerk Maxwell, one of the century’s most gifted mathematicians, who was able to use Faraday’s findings into mathematical equations, and more importantly, to conceive of the relationship between electricity, magnetism and light in a profoundly different way, to some extent anticipating the work of Einstein.

Canto: And we should leave it there, because we really hardly know what we’re talking about.

Jacinta: Too right – my reading up on this stuff brings my own ignorance to mind with the force of a very large electrostatic discharge….

now try these..

Written by stewart henderson

October 22, 2017 at 10:09 am

Why science?

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why is it so?

Ever since I was a kid I was an avid reader. It was my escape from a difficult family situation and a hatred or fear of most of my teachers. I became something of a quiet rebel, rarely reading what I was supposed to read but always trying to bite off more than I could chew in terms of literature, history, and occasionally science. I did find, though, that I could chew almost anything – especially in literature and history. And I loved the taste. Science, though, was different. It certainly didn’t come naturally to me. I didn’t know any science buffs and in fact I had no mentors for any of my reading activities. We did have encyclopaedias, though, and my random reading turned up the likes of Einstein, Newton, Darwin, Pasteur and other Big Names in science. Of course I was more interested in their bios than in the nature of their exotic researches, but in my idealised view they seemed very pure in their quest for greater understanding of the material world. I sometimes wished I could be like them but mostly I just dived into ‘literature’, a more comfortable world in which ordinary lives were anatomised by high-brow authors like Austen, Eliot and James (I had a fetish for 19th century lit in my teens). I took silent pride in my critical understanding of these texts, it surely set me above my classmates, though I remember one day walking home with one of the smartest kids in my class, who regaled me with his exploration of the electronics of a transistor radio he was pulling apart at home. I remember trying to listen, half ashamed of my ignorance, half hoping to change the subject to something I could sound off about.

Later, having dropped out of my much-loathed school, I started hanging out, or trying to, with other school drop-outs in my working-class neighbourhood. I didn’t fit in with them to say the least, but the situation worsened when they began tinkering with or talking about cars, which held no interest for me. I was annoyed and impressed at how articulate they were about carbies, distributors and camshafts, and wondered if I was somehow wasting my life.

Into my twenties, living la vie boheme in punk-fashionable poverty among art students and amateur philosophers, I read and was definitely intrigued by Alan Chalmers’ unlikely best-seller What is this thing called science? It sparked a brief interest in the philosophy of science rather than science itself, but interestingly it was a novel that really set me to reading and trying to get my head around science – a big topic! – on a more or less daily basis. I was about 25 when I read Thomas Mann’s The Magic Mountain, in which Hans Castorp, a young man of about my age at the time, was sent off to an alpine sanatorium to be cured of tuberculosis. Thus began a great intellectual adventure, but it was the scientific explorations that most spoke to me. Wrapped up in his loggia, reading various scientific texts, Castorp took the reader on a wondering tour of the origin of life, and of matter itself, and it struck me that these were the key questions – if you want to understand yourself, you need to understand humanity, and if you want to understand humanity you need to understand life itself, and if you want to understand life, you need to understand the matter that life is organised from, and if you need to understand matter…

I made a decision to inform myself about science in general, via the monthly magazine, Scientific American, where I learned at least something about oncogenes, neutrinos and the coming AIDS epidemic, inter alia. I read my first wholly scientific book, Dawkins’ The Selfish Gene, and, as I was still living la vie boheme, I enjoyed the occasional lively argument with housemates or pub philosophers about the Nature of the Universe and related topics. In the years since I’ve read and half-digested books on astronomy, cosmology, palaeontology and of course the history of science in general. I’ve read The origin of species, Darwin’s Voyage of the Beagle and at least four biographies of Darwin, including the monumental biography by Adrian Desmond and James Moore. I’ve also read a biography of Alfred Russell Wallace, and more recently, Siddhartha Mukherjee’s The Gene, which traces the search for the cause of the random variation essential to the Darwin-Wallace theory. And I still read science magazines like Cosmos on a more or less daily basis.

These readings have afforded me some of the greatest pleasures of my life, which would, I suppose, be enough to justify them. But I should try to answer the why question. Why is science so thrilling? The answer, I hope, is obvious. It isn’t science that’s thrilling, it’s our world. I’m not a science geek, it doesn’t come easily to me. When, for example, a tech-head explains how an electronic circuit works, I have to watch the video many times over, look up terms, refer to related videos, etc, in order to fix it in my head, and then, like most people, I forget the vast majority of what I read, watch or listen to. But what keeps me going is a fascination for the world – and the questions raised. How did the Earth form? Where did the water come from? How is it that matter is electrical, full of charge? How did language evolve? How has our Earth’s atmosphere evolved? How are we related to bananas, fruit flies, australopithecines and bats? How does our microbiome relate to obesity? What can we expect from CRISPR/Cas9 editing technology? What’s the future for autonomous vehicles, brain-controlled drones and new-era smart phones?

This all might sound like gaga adolescent optimism, but I’m only cautiously optimistic, or maybe not optimistic at all, just fascinated about what might happen, on the upside and the downside. And I’m endlessly impressed by human ingenuity in discovering new things and using those discoveries in innovative ways. I’m also fascinated, in a less positive way, by the anti-scientific tendencies of conspiracy theorists, religionists, new-agers and those who identify with and seem trapped by ‘heavy culture’. Podcasts such as The Skeptics’ Guide to the Universe, Skeptoid and Australia’s The Skeptic Zone, as well as various science-based blogs like Why Evolution is True and Skeptical Science are fighting a seemingly never-ending fight against the misinformation churned out by passionate supporters of fixed non-evidence-based positions. But spending too much time arguing with such types does your head in, and I prefer trying to accentuate the positive than trying to eliminate the negative.

And on that positive side, exciting things are always happening, whether it’s battery technology, cancer research, exoplanetary discoveries, robotics or brain implants, more developments are occurring than any one person can keep abreast of.

So I’ll end with some positive and reassuring remarks about science. It’s not some esoteric activity to be suspicious of, but neither is it something easily definable. It’s not a search for the truth, it’s more a search for the best, most comprehensive, most consistent and productive explanation for phenomena. I don’t believe there’s such a thing as the scientific method – the methods of Einstein can’t easily be compared with those of Darwin. Methods necessarily differ with the often vast differences between the phenomena under investigation. Conspiracy theories such as the moon landings ‘hoax’ or the climate science ‘fraud’ would require that scientists and their ancillaries are incredibly disciplined, virtually robotic collaborators in sinister plots, rather than normal, questing, competitive, collaborative, inspired and inspiring individuals, struggling desperately to make sense and make breakthroughs. In the field of human health, scientists are faced with explaining the most complex organism we know of – the human body with its often perverse human mind. It’s not at all surprising that pseudo-science and quackery is so common in this field, in which everyone wants to live and thrive as long as possible. But we need to be aware that with such complexity we will encounter many false hopes and only partial solutions. The overall story, though, is positive – we’re living longer and healthier, in statistical terms, than ever before. The past, for the most part, is another country which we might like to briefly visit, but we wouldn’t want to live there. And science is largely to be thanked for that. So, why not science? The alternatives do nothing for me.

The SGU team – science nerds fighting the good fight

Written by stewart henderson

October 7, 2017 at 6:18 am

three quite pleasurable little rants and rallies

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Bai Ping Ting

on Chinese women, fantasy and reality

I’ve been watching The General and I, a charming if generally ludicrous multi-million dollar Chinese historical fantasy series about a woman whose leadership abilities all men defer to. Fat chance of that happening in the real China, where the dictatorship of macho thugs has reigned supreme for decades. But could today’s fantasy – minus all the superhero powers – ever become tomorrow’s reality?

China, like every other country, has traditionally been highly patriarchal, and to be fair the dictatorship (I refuse to endorse the charade of calling the country a people’s republic) is moving with the times in calling for greater gender equality. However the political reality is clear. China’s dictatorship is essentially based on the nine members of the ‘Politburo Standing Committee of the Communist Party’, and of course these individuals are regularly replaced over time. No woman has ever been Standing (or even Sitting) on this Committee, and according to Wikipedia, ‘since 1997, China has fallen to 53rd place from 16th in the world in terms of female representation at its parliament, the National People’s Congress, according to the Inter-Parliamentary Union’.

Soong Ching-ling

It’s a disastrous situation, especially considering that in terms of women in the workforce, China is one of the world’s most egalitarian nations, outdoing the USA, Japan and many other developed countries. There seems to be little motivation to encourage women into the really important political jobs – the jobs they’d be best suited for as the more collaborative gender, and Angelababy’s Bai Ping Ting (actually not the most collaborative of females) is unlikely to change the situation. There doesn’t seem to be any woman of anywhere near the political stature of Cixi or Soong Ching-ling today. So I’d urge the smart women of China – there are millions of them – to rise up and demand their government to open its doors and let them in. They can’t do a Tianenman Square on you this time!

Cixi

 

on the archbishop of everywhere and nowhere

The same-sex marriage/marriage equality no-brainer has dragged on for far too long here. The other day I heard a fat archbishop of somewhere-or-other being introduced by the ABC to put the nope case. He started on about marriage being meant to be between a man and a woman, and I switched him off. Ahhh, but to have spent some time alone with him…Ok, I’d promise to have my hands tied behind my back. I’d ask him, how may female archbishops are there, mate? I mean, throughout history? In round figures? How many female bishops? Cardinals? Popes? You don’t think that’s relevant? Are you prepared to admit that your organisation’s hierarchy is extremely patriarchal? Like, the most patriarchal institution in the western world by a million miles? No, don’t blether on about your Mamma Superiors, I’m talking about the big decision-makers, you know that. And have you noticed how the most patriarchal societies in the world – look at the Middle East, Africa, parts of Asia and Eastern Europe – are also the most homophobic? You think that’s coincidence? Bullshit, patriarchy and homophobia hang together like a pair of testicles, and if you were a female archbishop, as you should be, you wouldn’t be sitting there spewing shit. But no, the Holy Roman Catholic and Apostolic Church would rather collapse under the weight of its own criminality than appoint a female to high office. So let me now turn to women everywhere, but especially to educated women who identify as Catholic. What the fuck are you thinking? How can you sleep at night? How can you more or less passively support the most retrograde and destructive institution in the western world? If you haven’t the sense to recognise your own interest, do it for other women, straight or gay, religious or no, and make a stand, surely you can do no other.

don’t ban, just abandon

 

on the history of marriage

‘Marriage has always been between a man and a woman, and I see no reason to change it.’ These, from memory, were the words of our former PM Julia Gillard, who was otherwise a good leader. Of course, even it it were true that marriage had always been between blokes and sheilas, that wouldn’t be sufficient reason to continue with that exclusive system. It’s a bit like saying ‘blacks have always had to sit at the back of the bus and use the back entrance and eat the leftovers…’ But has marriage always been between men and women (or little girls)? Or even between humans (I’m sure I’ve heard of a few blokes marrying horses and such). Who of us has witnessed the first marriage? Or the second or the fiftieth or the 500th? Where and when did they take place? Ten thousand years ago? Fifty thousand? Presumably at the time of mitochondrial Eve, some 180-200,000 years ago from memory, humans – and she was most definitely Homo sapiens – didn’t marry. There was little need for it as far as I can see, as there wouldn’t have been much in the way of property to protect and hand down to your legitimate heirs. And that’s interesting because, since mEve definitely had children, and we’re all descended from them, that makes us all bastards.

We don’t even know if humans were particularly monogamous at that time – we know sweet FA about their sexual liaisons, though it seems likely they were more free and easy than they are now – together with plenty of fighting over best mates. Of course the romantic in me likes to think that a twist of fate could’ve taken us the way of the bonobo, but there’s still time, and I’ll fight for that twist for the rest of my days. Meanwhile, marriage, if we must have it (and I’d rather not) is always what we make it, and making it as inclusive as possible is surely the best for us, and will maybe bring us full circle…

love isn’t blind, just blinkered

Written by stewart henderson

September 27, 2017 at 10:53 pm